Vienna Acoustics setup questions

Hi guys! I’m a frequent lurker round these parts who is assembling his first serious system piece by piece. Let me start by saying that I still wouldn’t consider myself an audiophile, but I do know what I like and have spent a fair bit of time in Home Audio stores here in town, listening. I’m still a little bit intimidated by the jargon and have lots to learn. If I do ask a stupid question and you think, “jeez, have you seen the search button?”, rest assured I have and am using it. I expect that half of this is going to just come out pretty stream-of-consciousness, giving rise to ever more questions.

Having listened to a friend’s Vienna Acoustics Mozarts, and then reading online and doing some listening to the VA line at Tweeter, I just fell in love with those speakers. About six months ago, I bought a Harman Kardon AVR 635 from Harman Direct for my 20’ X 25’ home theater setup(I’ll be primarily listening to music). I figured I’d get speakers used where possible and try to stretch the budget. I was hoping to get Mozarts for the fronts, with VA’s “Center” as my center and Haydns for the rears, with a to-be-named-later sub from REL, Velodyne or similar.

Saved a bit, and this weekend I’m shopping at the usual suspects online looking for my fronts—and found a pretty dadgum perfect set of Beethoven’s for $500 on craigslist right next to where I live. I ran down and grabbed ‘em super quick. So now, I’ve got a really sweet sounding stereo—and I haven’t done squat but plugged them in. Still need to place and tweak. But it’s got me in a bit of a tither, because these speakers were a bit out of my price range and I hadn’t really seriously considered them as part of my setup. What should I do next? Do you think the Harman Kardon is still enough to push them or should I look for an additional stereo amplifier to drive the Beethovens? If so, that’s something I haven’t really given any thought--any suggestions? I’m guessing I should probably move to the Theatro or Maestro for my center channel, but “Center” is still appealing for space considerations—I’d have to get creative to place the larger centers, maybe placing it above the plasma rather than below, and I fear it would just be a bit too overbearing—visually, anyway. I should be able to still use the smaller haydns for surrounds, but surrounds will be last on my list and is currently the least important in my mind. My teenage son plays a bass clarinet and is addicted to super-low wind instruments like the subcontrabass, so I’m thinking a subwoofer. Right now I’ve still got around 700 bucks leftover from my front speaker shopping, but never landed on a sub for my original setup—any specific suggestions there? I’ll be spending 1000-1500 every 4-6 months until I can get my dream setup. Funny, the wife won’t let me spend 4 grand on a complete system, but if I spend lots more over a couple of years it’s a “hobby” and she doesn’t mind a bit. :)